1. Field of the Invention
The present invention relates to a magnetic head suspension to be employed for a magnetic disk, i.e., a data storage device, and a method of fabricating such a magnetic head suspension.
2. Description of the Related Art
A magnetic head suspension included in a magnetic disk drive operates for reading information from and writing information to a magnetic disk. Magnetic head suspensions with wiring are used prevalently in recent years. Each magnetic head suspension holds a slider at its extremity. When two such magnetic head suspensions are used in combination, the magnetic head suspensions are spaced apart from each other by a suspension opening device, such as an opening tool or a robot arm, the magnetic head suspensions thus spaced apart are advanced toward a magnetic disk, and then the opening tool is removed from the magnetic head suspensions to let the sliders come into contact with the magnetic disk.
When the suspension opening device, such as an opening tool, is thus inserted in the space between the magnetic head suspensions to set the magnetic head suspensions on the magnetic disk, it is possible that the suspension opening device damages gold-plated wiring parts formed on the inner surfaces of the magnetic head suspensions. Therefore the gold-plated wiring parts are covered with a wiring protecting layer to protect the same from the possible damaging action of the suspension opening device.
The wiring protecting layer of the magnetic head suspension is formed, in most cases, of a liquid photosensitive resin, such as a photosensitive polyimide resin or a photosensitive epoxy resin. The wiring protecting layer is formed by applying a liquid photosensitive resin by a screen printing or a roll coating process to form photosensitive resin film on a workpiece. The workpiece is subjected to a drying process to remove the solvent from the photosensitive resin film, the resin film is exposed to light through a mask and the exposed resin film is developed to form a resin pattern, and, when necessary, the resin pattern is subjected to a hardening process.
When the wiring protecting layer of the magnetic head suspension is formed by processing the liquid photosensitive resin, it is difficult to apply the liquid photosensitive resin to a shaped workpiece having the shape of the suspension arm and provided with the wiring parts, and the drying process for removing the solvent needs additional time.
Some wiring protecting layers are formed from a photosensitive resin dry film containing a polyimide resin or a polyether-urethane resin. However, such a photosensitive resin dry film containing urethane bonds is not resistant to some chemicals, such as a flux cleaning agent, and is unsatisfactory in heat resistance.